Appendix H: Costing Information

Introduction

The information presented in this appendix has been taken from version 3 of a document titled "Structural Stormwater Quality BMP Cost / Size Relationship Information from the Literature" (Taylor, 2005b). The toolkit web site (www.toolkit.net.au) should be checked to see if this document has been subsequently updated.

This appendix summarizes cost-related information for structural stormwater quality best management practices (BMPs) that was found in the literature.

This information has been summarized to provide guidance to urban stormwater managers who are seeking additional costing information to that provided in MUSIC’s life cycle costing module. For example, a music user may wish to estimate the total acquisition cost of a very large plastic rainwater tank (e.g. 30 kL).  As the size / cost algorithm for this cost element in MUSIC’s life cycle cost module has been derived from a data set involving metal tanks that are 1 to 15 kL in size, the user is likely to use estimates from this appendix in preference to MUSIC’s default value.

Basic BMP cost / size relationships from the literature should be used with caution.  The CRC for Catchment Hydrology’s work involving BMP costing has found a very high degree of variability in most cost elements.  Despite this variability, very few cost-related studies report the degree of uncertainty associated with their cost estimates.

The dollar values quoted in this report have not been adjusted for inflation.  For example, if the referenced source of a cost estimate is "CRC (2002)", the dollar values are in 2002 Australian dollars.  At the time of writing, 2% is a suggested annual inflation rate that is relevant to these types of assets.

Gross Pollutant Traps

An in-ground GPT supplier undertook a survey of its units in NSW from October 1997 to September 2000.  The study looked at 334 maintenance events involving the removal of 1,345 tonnes of gross pollutants (in total).  This survey found that typical annual maintenance costs ranged from $0.13/kg (in 2001 dollars) for larger units to $0.28/kg for smaller units.  This range equates to approximately $0.17/ha/day to $0.78/ha/day.

The NSW EPA (2002) developed a spreadsheet that lists approximate unit prices (i.e. capital costs) for a wide range of proprietary GPTs.  This spreadsheet also provides some information on typical maintenance costs associated with these units.  A summary of these costs is provided below:

In addition, SIA (2004) reported that:

Boubli and Kassim (2003) reported the following cost estimates for supply and installation of above and below ground rainwater tanks or a single installation in Sydney:

Indicative prices for polyethylene (plastic) rainwater tanks are summarised below (Irrigation Warehouse, 2005).  These prices include GST, typically include delivery and are relevant to New South Wales, Victoria, southern Queensland and the Australian Capital Territory.

Grant and Hallmann (2003) estimated the costs associated with a 2,250 litre plastic tank with a life span of 30 years as: $510 purchase; $38.50 (delivery); $270 (for plumbing costs that allow toilet flushing and garden watering to use tank water); $350 (for the pump); $100 (electrician costs).  They also assumed the pump would last for 15 years, and the cost of running the pump (in Melbourne) was estimated to be $0.1368/kwh.

Additional Costs and Cost Break-downs

Melbourne Water (2003a) add 15% to estimated greenfield construction costs for "engineering fees" and 20% for "contingencies".

Brisbane City Council (2003) used the following assumption to break down total BMP construction costs where itemised costs were not available: 10% for design, 85% for construction and 5% for management costs.

Choi and Engel (2003) estimated that design costs for structural BMPs typically account for 30% of construction costs.

The Washington State Department of Transportation (2002) add 25% onto estimated BMP construction costs for "contingency" costs, 30% for "engineering services and permitting fees", and 10% for "mobilisation and demobilisation of equipment".

References

Barter, S. (2004). Senior Project Officer - Stormwater, Department of Environment and Conservation New South Wales, personal communication.

Beecham, S. (2002). Development of Water Sensitive Urban Design (WSUD) Concepts for Model Farms High School.  Not seen, cited in URS (2003).

Boral (2003). Costing data for porous paving in NSW.  Data provided in ‘Low Impact Water Management in New Developments - How Much Does WSUD Really Cost? Booklet 1: Project Cost Summaries and Workshop Information’ (Gibbs, S., Ed.). Booklet for the ‘How Much Does WSUD Really Cost?" workshop in Newcastle, 1 July 2003. Lower Hunter and Central Coast Regional Environmental Management Strategy, Newcastle, New South Wales.

Boubli, D. and Kassim, F. (2003). Comparison of Construction Costs for Water Sensitive Urban Design and Conventional Stormwater Design. Technical paper.  Available at: www.wsud.org (March 2005).

Brisbane City Council (2003). Unpublished cost estimates supplied by Emma Slack-Smith, Environmental Scientist, Brisbane, Queensland, personal communication.

Bryant, M. (2003). Senior Landscape Architect, Department of Public Works and Services, New South Wales, personal communication.  Data provided in ‘Low Impact Water Management in New Developments - How Much Does WSUD Really Cost? Booklet 1: Project Cost Summaries and Workshop Information’ (Gibbs, S., Ed.). Booklet for the ‘How Much Does WSUD Really Cost?" workshop in Newcastle, 1 July 2003. Lower Hunter and Central Coast Regional Environmental Management Strategy, Newcastle, New South Wales.

Cardno BLH (2002). Costing data for rainwater tanks.  Data provided in ‘Low Impact Water Management in New Developments - How Much Does WSUD Really Cost? Booklet 1: Project Cost Summaries and Workshop Information’ (Gibbs, S., Ed.). Booklet for the ‘How Much Does WSUD Really Cost?" workshop in Newcastle, 1 July 2003. Lower Hunter and Central Coast Regional Environmental Management Strategy, Newcastle, New South Wales.

Centre for Watershed Protection (CWP) (1998). Costs and Benefits of Storm Water BMPs: Final Report 9/14/98.  Centre for Watershed Protection, Ellicott City, Maryland; not seen, cited in US EPA (2001).

Choi, J.Y. and Engel, B.A. (2003). Cost Analysis System for Urban Storm Water BMPs (CASUB).  Cited at: http://danpatch.ecn.purde.edu/~sprawl/LTHIA7/ubmp0/cost0.htm (4 November 2003).

Coombes, P. (2002). Practice Note No. 4 - Rainwater Tanks.  Lower Hunter and Central Coast Regional Environmental Management Strategy, Newcastle, New South Wales.

Earth Tech Engineering Pty Ltd (2003). Unpublished cost estimate supplied by Lisa Stevens, Engineering Designer, Shepparton, Victoria, personal communication.

Fletcher, T., Duncan, H., Lloyd, S, and Poelsma, P. (2005). Stormwater Flow and Quality and the Effectiveness of Non-proprietary Stormwater Treatment Measures.  Technical Report 04/8.  Cooperative Research Centre for Catchment Hydrology, Melbourne, Victoria.

Gardner, T. (2004).  Principal Scientist - Water Cycle Sciences, Department of Natural Resources, Queensland, personal communication.

Gardner, T., Millar, G. and Hyde, R. (2003). ‘The Healthy Homeâ - A Step Towards Sustainable Suburbs’.  Proceedings of the Second National Water Recycling Conference. Brisbane, September 2003.

Gibbs, S. (2003). Low Impact Water Management in New Developments - How Much Does WSUD Really Cost? Booklet 1: Project Cost Summaries and Workshop Information. Booklet for the ‘How Much Does WSUD Really Cost?" workshop in Newcastle, 1 July 2003. Lower Hunter and Central Coast Regional Environmental Management Strategy, Newcastle, New South Wales.

Grant, T. and Hallmann, M. (2003). ‘Urban Domestic Water Tanks: Life Cycle Assessment’. Water, August 2003, pp. 22-27.

Hornsby Shire Council (2002). The Catchment Remediation Capital Works Program - Annual Report 2001 - 2002. Hornsby Shire Council, Hornsby, New South Wales.

Hunter, G. (2003). Engineering Coordinator - Stormwater, Penrith City Council, New South Wales, personal communication.  Data provided as part of the CRC’s BMP costing survey of Australian stormwater managers.

Institute for Sustainable Futures (2002). Kogarah Town Square Water Management - An Evaluation of Costs and Benefits.  Report prepared for Kogarah Municipal Council.  Institute for Sustainable Futures, University of Technology, Sydney, New South Wales.

Irrigation Warehouse (2005). Web site for water tanks models and prices. Available at: www.irrigationwarehouse.com.au/category248_1.htm (March 2005).

Kuczera G. and Coombes, P. (2001). A System Perspective of the Urban Water Cycle: New Insights, New Opportunities. Paper presented at the Stormwater Industry Association 2001 Regional Conference. Port Stephens, New South Wales, 26-28 April 2001.

Lane, H. (2004). ‘Water Sensitive Urban Design in the Snowy Monaro Region’. Proceedings of the SIA 2004 Regional Conference: Use It or Lose It - It Makes Sense. Shoalhaven, New South Wales.

Leinster, S. (2004). Shaun Leinster, Senior Engineer, Ecological Engineering Pty Ltd, Brisbane, Queensland, personal communication.

Lloyd, S.D., Wong, T.H.F, and Chesterfield, C.J. (2002).  Water Sensitive Urban Design - A Stormwater Management Perspective. Industry Report No. 02/10. Cooperative Research Centre for Freshwater Ecology, Melbourne, Victoria. Referenced heavily in Fletcher et al. (2005).

Melbourne Water (2003a). Unpublished cost estimation model for large greenfield wetlands funded by Melbourne Water.  Melbourne Water, Melbourne, Victoria.

Melbourne Water (2003b). Rainwater Tanks > Maintenance and Costs. Web page within the ‘Integrated Water Cycle Tools’ web site.  Available at: http://wsud.melbournewater.com.au/content/integrated/raintanks+3.htm (September 2003).

New South Wales Department of Public Works and Services (2001). Conceptual Design Report for Stormwater Pollution Abatement at Blackwattle Bay.  Dams and Civil, Rozelle Bay, New South Wales.

New South Wales Environmental Protection Authority (NSW EPA) (2000). Unpublished costing data for structural stormwater quality BMPs derived from NSW local governments.  Dated February 2000. NSW EPA, Sydney, New South Wales.

Newcastle City Council (2002). Newcastle City Council final report to the NSW Stormwater Trust. Data provided in ‘Low Impact Water Management in New Developments - How Much Does WSUD Really Cost? Booklet 1: Project Cost Summaries and Workshop Information’ (Gibbs, S., Ed.). Booklet for the ‘How Much Does WSUD Really Cost?" workshop in Newcastle, 1 July 2003. Lower Hunter and Central Coast Regional Environmental Management Strategy, Newcastle, New South Wales.

Standards Australia (1999). AS/NZS 4536:1999 Life cycle Costing - An Application Guide. Standards Australia, Homebush, NSW.

Stormwater Industry Association (SIA) (2004). Water Tank Savings. Available at: www.stormwater.asn.au/tanks/tanksavings.htmlrl (August 2004).

Taylor, A.C. (2003). An Introduction to Life cycle Costing Involving Structural Stormwater Quality Management Measures. Technical Paper. Cooperative Research Centre for Catchment Hydrology, Melbourne, Victoria. Available at: www.catchment.crc.org.au (August 2004).

Taylor, A.C. and Wong, T.H.F. (2002). Non-structural Stormwater Quality Best Management Practices - A Literature Review of Their Value and Life cycle Costs. Technical Report 02/13, Cooperative Research Centre for Catchment Hydrology, Melbourne, Victoria. Available at: www.catchment.crc.org.au (March 2005).

United States Environmental Protection Agency (US EPA) (2001). National Menu of Best Management Practices for Storm Water Phase II. United States Environmental Protection Agency on-line guideline: www.epa.gov/npdes/menuofbmps/menu.htm (August 2004).

URS (2003). Water Sensitive Urban Design Technical Guidelines for Western Sydney. Draft report prepared for the Upper Parramatta River Catchment Trust, Sydney, New South Wales.

Walsh, G. (2001). Gary Walsh, Senior Engineer, Melbourne Water, Victoria, personal communication.  Cited in Taylor and Wong (2002).

Washington State Department of Transportation (2002). Stormwater Management for Highway Improvement Projects in Western Washington. Washington State Department of Transportation, Washington.

WBM Oceanics (2003). Stormwater Treatment Framework and Stormwater Quality Improvement Device Guidelines - Exhibition Draft - Version 3.  Not seen, cited in URS (2003).

Weber, T. (2001) & (2002). Tony Weber, Senior Waterways Program Officer (Water Quality), Brisbane City Council, Queensland, personal communication.  Cited in Taylor and Wong (2002).

[1]   Note that true life cycle costing in accordance with the relevant Australian Standard (Standards Australia, 1999) considers more than just construction/purchase cost and typical annual maintenance cost.  For more information see Taylor (2003).  Also, these approximate costs will vary with time and location.  For up-to-date costs of proprietary units, contact the GPT supplier.

[2]   That is, a sediment basin with a trash rack.